This Airtech Advanced locking ring is designed to be used with Maxx CNC Hop Up Units to improve consistency and accuracy.

The brass ring which sits between the end of the hop unit and inner barrel tends to leave a gap which allows the barrel to be tilted at an angle.

This improved design replaces the stock Maxx O-ring (normally brass) at the end of setting up the hop unit.

Once the new o-ring is installed, it will ensure a snug fit to restrict the motion of the barrel within the hop-up chamber. It will secure the inner barrel in the true horizontal position. Even when shots are fired, which is the moment where there is the most stress and vibration at the hop-up, the O-ring will ensure the structure is intact.

This creates a dependable system for the BB to travel down the barrel undisturbed for the most consistent and accurate shots.

The end of the locking ring is extended to give a longer locking surface to shim the inner barrel against the inside of the hop chamber. Silicone o-rings are included to give a tight fit with the lower receiver and further restrict movement and vibration when shooting.

Installation notes
If the ring is a too tight for your inner barrel, lightly sand the inside of the ring and test fit in small increments until a snug fit is achieved.